KR101192276B1 - Carboxylic acid modified-nitrile based copolymer latex for dip-forming, latex composition for dip-forming comprising the same - Google Patents

Abstract

The present invention relates to a carboxylic acid-modified nitrile-based copolymer latex comprising an unsaturated monomer having a ureido group as a crosslinkable functional group, a latex composition for dip molding comprising the same, and a molded article prepared therefrom. By adding unsaturated monomers having ureido groups as crosslinkable functional groups instead of sulfur or vulcanization accelerators, which are added for the purpose, long stirring aging process due to sulfur or vulcanization accelerators is not necessary, and no allergic reactions are caused, and oil resistance and mechanical strength are high and soft. It is possible to manufacture molded articles having a touch.

Crosslinkable functional group * ureido * carboxylic acid modified copolymer * latex * dip molding * molded product *

Description

Carboxylic acid modified-nitrile based copolymer latex for dip-forming, latex composition for dip-forming forming the same}

The present invention relates to a carboxylic acid-modified nitrile copolymer latex comprising an unsaturated monomer having a ureido group as a crosslinkable functional group, a latex composition for dip molding comprising the same, and a dip molded article prepared therefrom.

Rubber gloves are used in a wide range of fields such as household, food, electronics, and medical fields. In the meantime, rubber gloves made by dip molding natural rubber latex have been used a lot, but the protein contained in the natural rubber causes problems in some users due to allergic reactions such as pain or rash.

As a result, sulfur and vulcanization accelerators are added to a synthetic rubber latex that does not cause an allergic reaction, for example, a carboxylic acid-modified nitrile copolymer latex such as acrylic acid-acrylonitrile-butadiene copolymer latex. Many gloves made by dip molding the blended latex composition have been used.

However, in the process of producing such gloves, there is a problem in that productivity is lowered because a long stirring maturation process of 24 hours or more is required after the combination of sulfur and vulcanization accelerator to latex for crosslinking of the nitrile rubber.

In addition, when working with rubber gloves made from a composition containing sulfur and a vulcanization accelerator as an essential component for a long time, an odor caused by sulfur may be unpleasant, or the color of the gloves may be discolored, resulting in deterioration of product value. There was a problem causing allergic reactions and stinging. In general, a vulcanization accelerator containing zinc is added for ionic crosslinking in the carboxyl period. However, this has a problem that the water resistance of the glove is lowered.

In Japanese Patent Laid-Open No. 2006-321955, a method for obtaining a dip molded product without using sulfur and a vulcanization accelerator is used to remove a long stirring aging process by using a latex composition for deep molding including a conjugated diene rubber latex and an organic peroxide. Although it can be used to make gloves that do not discolor, there is a disadvantage that the organic peroxide solution is very harmful to the human body and is not safe because of the danger of fire and explosion when heat or impact is applied.

In US Pat. No. 7,345,111, a crosslinkable monomer is used in acrylic emulsion latex to make a glove which does not have a long stirring aging process and does not cause an allergic reaction by sulfur and vulcanization accelerators, but an acrylic glove has the disadvantage of being too sensitive to temperature.

Therefore, in the present invention to solve the problems of the prior art as described above, the object of the present invention is to add a sulfur or vulcanization accelerator for the crosslinking of the nitrile rubber, there is no long stirring aging process, without causing an allergic reaction, The final molded article is to provide a carboxylic acid-modified nitrile copolymer latex having a similar oil resistance, mechanical strength, and soft touch.

In addition, another object of the present invention is to provide a latex composition for dip molding comprising the carboxylic acid-modified nitrile copolymer latex and molded articles prepared therefrom.

In the present invention, in the preparation of the carboxylic acid-modified nitrile copolymer latex, the final molded article prepared by using an unsaturated monomer having a ureido group as a crosslinkable functional group in place of sulfur or vulcanization accelerator, which is usually added to perform the role of a crosslinking agent. While maintaining physical properties at a similar level as in the prior art, it can be confirmed that there is no long agitation aging process and the occurrence of allergies, thereby solving the conventional problems as described above.

By using a carboxylic acid-modified nitrile copolymer latex prepared using an ureido group unsaturated monomer having a crosslinkable functional group in the glove manufacturing process as in the present invention, there is no long stirring aging process, and allergic reaction by sulfur and vulcanization accelerators is not caused. In addition, while maintaining physical properties such as oil resistance and mechanical strength at a conventional level, it is possible to manufacture a molded article having a soft touch.

The carboxylic acid-modified nitrile copolymer latex of the present invention for achieving the above object is characterized in that it comprises an unsaturated monomer having a ureido group as a crosslinkable functional group.

In addition, the carboxylic acid-modified nitrile-based copolymer latex composition for achieving another object of the present invention is one or more additives selected from the group consisting of a vulcanization catalyst, a pigment, a filler, a thickener and a pH adjusting agent to the carboxylic acid-modified nitrile-based copolymer It characterized by including the.

In addition, a dip molded article for achieving another object of the present invention is characterized by being obtained by dip molding the composition.

Hereinafter, the present invention will be described in more detail.

The present invention is prepared by adding an emulsifier, a polymerization initiator, and a molecular weight regulator to each monomer constituting the carboxylic acid-modified nitrile copolymer, to prepare a carboxylic acid-modified nitrile copolymer latex, which is then included in a dip molding latex composition Molding produces the final product.

Hereinafter, the carboxylic acid-modified nitrile copolymer latex and latex composition including the latex used to obtain the dip molded article of the present invention will be described in detail.

1.Carboxylic Acid Modified Nitrile Copolymer Latex

The carboxylic acid-modified nitrile copolymer latex according to the present invention is prepared by emulsion polymerization by adding an emulsifier, a polymerization initiator, a molecular weight regulator, and other additives to each monomer constituting the carboxylic acid-modified nitrile copolymer.

Each monomer constituting the carboxylic acid-modified nicrylic copolymer is 40 to 90% by weight conjugated diene monomer, 10 to 50% by weight ethylenically unsaturated nitrile monomer, 0.1 to 10% by weight ethylenically unsaturated acid monomer, and ureido group 0.1 to 10% by weight of an unsaturated monomer having a crosslinkable functional group.

Here, the unsaturated monomer having the ureido group as a crosslinkable functional group serves as a crosslinking agent for crosslinking the monomers as in the conventional sulfur or vulcanization accelerator, and in the present invention, the nitrile-based rubber can be crosslinked without sulfur or vulcanization accelerator. . Specific examples of the unsaturated monomer containing such ureido groups include 2-ethylene ureidoethyl methacrylate, 2-ethylene ureidoethyl methacrylamide and bis (2-ethylene ureidoethyl) maleate. These compounds may be used alone or in combination of two or more thereof.

As for the content of the unsaturated monomer which has the said ureido group as a crosslinkable functional group, it is preferable to use 0.1-5 weight% in carboxylic acid modified nitrile copolymer latex, More preferably, use 0.3-3 weight%. . If the amount of the crosslinkable monomer is less than 0.1% by weight, the tensile strength of the dip molded product is lowered, and if it is greater than 5% by weight, the touch and fit are poor.

That is, in the case of an unsaturated monomer having a ureido group according to the present invention as a crosslinkable functional group, the monomers can be crosslinked to ensure excellent physical properties in the final manufactured dip molded product. Such physical properties are prepared by adding sulfur or a vulcanization accelerator. Is equivalent to or better than the equivalent dip molding.

In addition, since a long stirring aging process of more than 24 hours is not necessary for sufficient crosslinking after adding sulfur or a vulcanization accelerator, and there is no allergy caused by this, gloves used as a dip molded article of a preferred embodiment of the present invention are used for a long time. There are many problems that can be solved.

Specific examples of the conjugated diene monomer constituting the carboxylic acid-modified nitrile rubber copolymer include 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, At least one selected from the group consisting of 1,3-pentadiene and isoprene, of which 1,3-butadiene and isoprene are preferable, and 1,3-butadiene is most preferably used.

The conjugated diene monomer is included 40 to 90% by weight, preferably 45 to 80% by weight of the total monomer constituting the carboxylic acid-modified nitrile copolymer. If the content of the conjugated diene monomer is less than 40% by weight, the dip molded product becomes hard and the wear is poor. When the conjugated diene monomer content is more than 90% by weight, the oil resistance of the dip molded product is deteriorated and the tensile strength is lowered.

The ethylenically unsaturated nitrile monomer constituting the carboxylic acid-modified nitrile rubber copolymer is selected from the group consisting of acrylonitrile, methacrylonitrile, fumaronitrile, α-chloronitrile, and α-cyano ethyl acrylonitrile. Among them, at least one of them is preferred, among which acrylonitrile and methacrylonitrile are preferred, and acrylonitrile is particularly preferably used.

The ethylenically unsaturated nitrile monomer constituting the carboxylic acid-modified nitrile rubber copolymer is included in an amount of 10 to 50% by weight, preferably 15 to 45% by weight, of all monomers constituting the carboxylic acid-modified nitrile copolymer. If the ethylenically unsaturated nitrile monomer content is less than 10% by weight, the oil resistance of the dip molded product is poor, the tensile strength is lowered, and if it is more than 50% by weight, the dip molded product is hard and the wear feeling is poor.

In addition, the ethylenically unsaturated acid monomer is an ethylenically unsaturated monomer containing at least one acidic group selected from the group consisting of a carboxyl group, a sulfonic acid group, and an acid anhydride group, for example, acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, or the like. Ethylenically unsaturated carboxylic acid monomers; Polycarboxylic acid anhydrides such as maleic anhydride and citraconic anhydride; Ethylenically unsaturated sulfonic acid monomers such as styrene sulfonic acid; And ethylenically unsaturated polycarboxylic acid partial ester monomers such as monobutyl fumarate, monobutyl maleate, and mono-2-hydroxypropyl maleate. It is preferable to use an ethylenic unsaturated carboxylic monomer among these, and methacrylic acid is especially preferable. Such ethylenically unsaturated acid monomers may be used in the form of alkali metal salts or ammonium salts.

The ethylenically unsaturated acid monomer is included in 0.1 to 10% by weight, preferably 0.5 to 9% by weight, more preferably 1 to 8% by weight of the total monomers constituting the carboxylic acid-modified nitrile copolymer. If the content of the ethylenically unsaturated acid monomer is less than 0.1% by weight, the tensile strength of the dip molded article is lowered, and if it is more than 10% by weight, the dip molded article is hardened and wear is poor.

The carboxylic acid-modified nitrile copolymer according to the present invention may optionally further include other ethylenically unsaturated monomers copolymerizable with the ethylenically unsaturated nitrile monomer and the ethylenically unsaturated acid monomer, specifically styrene and alkyl styrene. And vinyl aromatic monomers selected from the group consisting of vinyl naphthalene; Fluoroalkyl vinyl ethers such as fluoro ethyl vinyl ether; (Meth) acrylamide, N-methylol (meth) acrylamide, N, N-dimethylol (meth) acrylamide, N-methoxy methyl (meth) acrylamide, and N-propoxy methyl (meth) acrylamide Ethylenically unsaturated amide monomers selected from the group consisting of: Vinyl pyridine; Vinyl norbornene; Non-conjugated diene monomers such as dicyclopentadiene and 1,4-hexadiene; Methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, dibutyl maleate, difumaric acid Butyl, diethyl maleate, methoxy methyl (meth) acrylate, ethoxy ethyl (meth) acrylate, methoxy ethoxy ethyl (meth) acrylate, cyano methyl (meth) acrylate, 2-cyano ethyl (meth) acrylate, (Meth) acrylic acid 1-cyanopropyl, (meth) acrylic acid 2-ethyl-6-cyanohexyl, (meth) acrylic acid 3-cyanopropyl, (meth) acrylic acid hydroxyethyl, (meth) acrylic acid hydroxyethyl, Consisting of ethylenically unsaturated carboxylic ester monomers selected from the group consisting of (meth) acrylic acid hydroxy propyl, glycidyl (meth) acrylate, and dimethylamino ethyl (meth) acrylate It was used as the at least one selected from the.

The amount of the ethylenically unsaturated monomer may be used within 20% by weight of the total monomers constituting the carboxylic acid-modified nitrile copolymer, and when it exceeds 20% by weight, there is a poor balance between soft fit and tensile strength.

The carboxylic acid-modified nitrile copolymer latex of the present invention can be produced by emulsion polymerization by adding an emulsifier, a polymerization initiator, a molecular weight modifier and the like to the monomers constituting the carboxylic acid-modified nitrile copolymer.

Although it does not specifically limit as an emulsifier, For example, anionic surfactant, a nonionic surfactant, cationic surfactant, an amphoteric surfactant, etc. can be used. Among them, anionic surfactants selected from the group consisting of alkylbenzene sulfonates, aliphatic sulfonates, sulfuric acid ester salts of higher alcohols, α-olefin sulfonate salts, and alkyl ether sulfuric acid ester salts may be particularly preferably used. The amount of the emulsifier to be used is preferably 0.3 to 10 parts by weight, more preferably 0.8 to 8 parts by weight based on 100 parts by weight of the monomer constituting the carboxylic acid-modified nitrile copolymer.

Although it does not specifically limit as a polymerization initiator, A radical initiator can be used preferably. As a radical initiator, inorganic peroxides, such as sodium persulfate, potassium persulfate, ammonium persulfate, potassium perphosphate, hydrogen peroxide; t-butyl peroxide, cumene hydroperoxide, p-mentanehydro peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, acetyl peroxide, isobutyl peroxide, octanoyl peroxide, dibenzoyl peroxide Organic peroxides such as oxides, 3,5,5-trimethylhexanol peroxide, t-butyl peroxy iso butyrate; At least one selected from the group consisting of azobis isobutyronitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, and azobis iso butyric acid (butyl acid) methyl, and among these radical initiators Inorganic peroxide is more preferable, and persulfate can be used especially preferably. The amount of the polymerization initiator used is preferably 0.01 to 2 parts by weight, more preferably 0.02 to 1.5 parts by weight based on 100 parts by weight of all monomers constituting the carboxylic acid-modified nitrile copolymer.

Although it does not specifically limit as a molecular weight modifier, For example, Mercaptans, such as (alpha) -methylstyrene dimer, t-dodecyl mercaptan, n-dodecyl mercaptan, octyl mercaptan; Halogenated hydrocarbons such as carbon tetrachloride, methylene chloride and methylene bromide; Sulfur-containing compounds, such as tetraethyl thiuram disulfide, dipentamethylene thiuram disulfide, and diisopropyl chianthogen disulfide, etc. are mentioned. These molecular weight modifiers may be used alone or in combination of two or more thereof. Among these, mercaptans are preferable, and t-dodecyl mercaptan can be used more preferably. Although the usage-amount of a molecular weight modifier changes with the kind, Preferably it is 0.1-0.9 weight part, More preferably, it is 0.2-0.7 weight part with respect to 100 weight part of the monomers which comprise the said carboxylic acid modified nitrile copolymer. .

As the polymerization terminator, for example, hydroxyl amine, hydroxy amine sulfate, diethyl hydroxy amine, hydroxy amine sulfonic acid and its alkali metal ions, sodium dimethyl dithio Aromatic hydroxy dithio carboxylic acids, such as a carbamate, a hydroquinone derivative, hydroxy diethyl benzene dithio carboxylic acid, and hydroxy dibutyl benzene dithio carboxylic acid, etc. are mentioned. Although the usage-amount of a polymerization terminator is not specifically limited, It is 0.1-2 weight part with respect to 100 weight part of all monomers through.

In addition, during the polymerization of the latex of the present invention, if necessary, additives such as chelating agent, dispersing agent, pH adjusting agent, deoxygenating agent, particle size adjusting agent, anti-aging agent, oxygen scavenger and the like can be added.

The method of adding the monomer mixture constituting the carboxylic acid-modified nitrile copolymer is not particularly limited, and the method of introducing the monomer mixture into the polymerization reactor at once, the method of continuously introducing the monomer mixture into the polymerization reactor, and a part of the monomer mixture May be added to the polymerization reactor, and any method of continuously supplying the remaining monomers to the polymerization reactor may be used.

Although the polymerization temperature at the time of the said emulsion polymerization is not specifically limited, Usually, 10-90 degreeC, Preferably it is 25-75 degreeC. The conversion rate at the time of stopping a polymerization reaction becomes like this. Preferably it is 90% or more, More preferably, it is 93% or more. By removing the unreacted monomer and adjusting the solid content concentration and pH can be obtained a carboxylic acid-modified nitrile copolymer latex.

2. Latex Composition for Dip Molding

The latex composition for dip molding may be prepared by including at least one additive selected from the group consisting of pigments, fillers, thickeners and pH adjusting agents in the carboxylic acid-modified nitrile copolymer latex of the present invention obtained by the above method.

In addition, the latex composition for dip molding may use subsidiary materials such as chelating agent, dispersing agent, deoxygenating agent, particle size adjusting agent, anti-aging agent, oxygen scavenger and the like as necessary.

The carboxylic acid-modified nitrile copolymer latex in the composition is preferably 80 to 99% by weight, preferably 85 to 97% by weight of the total composition in terms of glove properties, which is a kind of dip molded product of the present invention.

Solid concentration of the latex composition for dip molding of the present invention is preferably 10 to 40% by weight, more preferably 15 to 35% by weight. As for pH of the latex composition for dip molding of this invention, 8.0-12 are preferable and 9-11 are more preferable.

3. Dip molded products

As a dip molding method for obtaining the dip molded article of the present invention, a conventional method can be used, and examples thereof include a direct dipping method, an anode adhesion dipping method, and a Teague adhesion dipping method. Among them, an anode adhesion dipping method is preferable because of the advantage that a dip molded article having a uniform thickness can be easily obtained.

Hereinafter, the method of manufacturing a dip molded article using the latex composition of this invention is demonstrated in detail.

(a) dipping the hand-shaped dip mold into the coagulant solution to attach the coagulant to the surface of the dip mold;

Examples of coagulants include metal halides such as barium chloride, calcium chloride, magnesium chloride, zinc chloride and aluminum chloride; Nitrates such as barium nitrate, calcium nitrate and zinc nitrate; Acetates such as barium acetate, calcium acetate and zinc acetate; Sulfates such as calcium sulfate, magnesium sulfate and aluminum sulfate. Of these, calcium chloride and calcium nitrate are preferred. The coagulant solution is a solution in which such coagulant is dissolved in water, alcohol or a mixture thereof. The concentration of coagulant in the coagulant solution is usually 5 to 75% by weight, preferably 15 to 55% by weight.

(b) immersing the dip molding mold to which the coagulant is attached to the latex resin composition of the present invention to form a dip molding layer

The dip molding machine to which a coagulant is stuck is immersed in the latex composition for dip molding made from the latex resin composition of the present invention, and then the dip molding machine is taken out to form a dip molding layer in the dip molding machine.

(c) cross-linking the latex resin by heating the dip molding layer formed on the dip molding die;

In the heat treatment, the water component evaporates first and curing through crosslinking is performed. Subsequently, the dip molding layer crosslinked by heat treatment is peeled off from the dip mold to obtain a dip molded product.

(d) measuring the physical properties of the obtained dip molding

A dumbbell-shaped test piece was produced from the obtained dip molded product in accordance with ASTM D-412. Subsequently, the specimen was pulled at a stretching speed of 500 mm / min using a UTM (Universal Testing Machine), the tensile strength and elongation at break were measured, and the touch was measured by the stress when the elongation was 300%. The higher the tensile strength and elongation, the better the quality of the deep molded product, and the lower the stress value when the elongation is 300%, the better the feel of the deep molded product.

The process according to the invention can be used for any latex article which can be produced by the technically known dip-molding method. Specifically, it can be applied to dip molded latex articles selected from health care products such as surgical gloves, inspection gloves, condoms, catheters or various kinds of industrial and household gloves.

Hereinafter, the present invention will be described in detail by Examples and Comparative Examples. The following examples are provided to illustrate the present invention, and the scope of the present invention includes the scope defined by the following claims, modifications and substitutions thereof, and is not limited to the scope of the present examples.

Example 1

(Manufacture of latex for dip molding)

Agitator, thermometer, cooler, inlet of nitrogen gas and 10L high pressure reactor equipped to continuously input monomer, emulsifier, polymerization initiator with nitrogen, followed by 29% by weight of acrylonitrile, 1,4-butadiene 66 2 parts by weight of sodium alkyl benzene sulfonate, 0.5 parts by weight of t-dodecyl mercaptan with respect to 100 parts by weight of a monomer mixture of 1% by weight, 4% by weight of methacrylic acid, 1% by weight of bis (2-ethyleneureidoethyl) maleate, and 140 weight part of ion-exchange water was thrown in, and it heated up to 40 degreeC.

After the temperature was raised, 0.3 parts by weight of potassium persulfate as a polymerization initiator was added, and when the conversion rate reached 95%, 0.1 parts by weight of sodium dimethyl dithio carbamate was added to terminate the polymerization. The unreacted monomer was removed through a deodorizing process, and ammonia water, an antioxidant, an antifoaming agent, and the like were added to obtain a carboxylated acrylonitrile-butadiene copolymer latex having a solid concentration of 45% and a pH of 8.5.

 (Production of Dip Molding Composition)

A 3% potassium hydroxide solution and an appropriate amount of secondary distilled water were added to the latex to obtain a dip molding composition having a solid concentration of 25% and a pH of 10.0.

(Dip molding product manufacturing)

A coagulant solution was prepared by mixing 22 parts by weight of calcium nitrate, 69.5 parts by weight of distilled water, 8 parts by weight of calcium carbonate, and 0.5 parts by weight of wetting agent (Teric 320 produced by Huntsman Corporation, Australia). The hand-shaped ceramic mold was immersed in this solution for 1 minute, taken out, and dried at 80 ° C. for 3 minutes to apply a coagulant to the hand-shaped mold.

Next, the mold to which the coagulant was apply | coated was immersed in the said dip molding composition for 1 minute, pulled up, it dried for 1 minute at 80 degreeC, and soaked for 3 minutes in water or hot water. The mold was dried at 80 ° C. for 3 minutes and crosslinked at 130 ° C. for 20 minutes. The crosslinked dip molding layer was peeled off from the hand-shaped mold to obtain a dip molded article in the form of a glove. The physical properties of this dip molded article are shown in Table 1.

Example 2

Except for using 3% by weight instead of 1% by weight of bis (2-ethylene ureidoethyl) maleate monomer in Example 1 and 27% by weight instead of 29% by weight of acrylonitrile, the composition for dip molding and A dip molded article in the form of a glove was prepared, and the physical properties thereof are shown in Table 1.

Example 3

Except for using 5% by weight instead of 1% by weight of bis (2-ethylene ureidoethyl) maleate monomer in Example 1 and 25% by weight instead of 29% by weight of acrylonitrile composition for dip molding and A dip molded article in the form of a glove was prepared, and the physical properties thereof are shown in Table 1.

Example 4

A dip molding composition and a glove form dip in the same manner as in Example 1 except that 1 wt% of 2-ethyleneureidoethyl methacrylate was used instead of 1 wt% of bis (2-ethyleneureidoethyl) maleate monomer. Molded articles were prepared, and the physical properties are shown in Table 1.

Example 5

Except that in Example 1 3% by weight of 2-ethyleneureidoethyl methacrylate was used instead of 1% by weight of bis (2-ethyleneureidoethyl) maleate monomer and 27% by weight instead of 29% by weight of acrylonitrile. In the same manner, a dip molding composition and a dip molded article in the form of a glove were manufactured, and the physical properties thereof are shown in Table 1.

Example 6

Example 1 1% by weight of bis (2-ethyleneureidoethyl) maleate monomer and 1% by weight of 2-ethyleneureidoethyl methacrylate instead of 1% by weight of bis (2-ethyleneureidoethyl) maleate monomer A dip molding composition and a glove-shaped dip molded article were prepared in the same manner except that 28 wt% of acrylonitrile was used instead of 29 wt%, and the physical properties thereof are shown in Table 1.

Comparative Example 1

Except for using a bis (2-ethylene ureidoethyl) maleate monomer in Example 1, 30% by weight of acrylonitrile was prepared in the same manner as the dip molding composition and glove-shaped dip molded article, Physical properties are shown in Table 1.

The physical properties of each of the moldings prepared in Examples and Comparative Examples were evaluated as follows, and the results are shown in Table 1 below.

Tensile strength, elongation, modulus at 300% elongation: Dumbbell shaped specimens were prepared according to ASTM D-412. Subsequently, the specimen was pulled at an elongation rate of 500 mm / min, and the stress at 300% elongation, the tensile strength at break and the elongation at break were measured.

Tensile Strength (MPa) Elongation (%) Stress at 300% (MPa) Example 1 23.5 650 3.7 Example 2 24.5 610 3.6 Example 3 24.5 550 4.5 Example 4 22.5 690 3.5 Example 5 22.8 610 3.5 Example 6 23.6 620 3.2 Comparative Example 1 10.5 700 2.7

As a result of Table 1, the dip molded article according to Examples 1 to 6 prepared by adding a carboxylic acid-modified nitrile-based latex prepared by adding a compound containing a ureido group as a crosslinkable functional group from a composition that does not include this It can be confirmed that the stress properties when the tensile strength and elongation of 300% compared to the prepared Comparative Example 1. That is, in the present invention, it is confirmed that the final product can secure the physical properties required for the dip molded product by effectively crosslinking the nitrile rubber without the addition of sulfur or vulcanization accelerator, which was added in the prior art, for the crosslinking of the nitrile rubber. have.

Claims (13)

In the carboxylic acid-modified nitrile copolymer latex for dip molding containing a conjugated diene monomer, an ethylenically unsaturated nitrile monomer, an ethylenically unsaturated acid monomer, and a crosslinkable monomer, 40 to 89% by weight of the conjugated diene monomer, 10 to 50% by weight of the ethylenically unsaturated nitrile monomer, 0.1 to 10% by weight of the ethylenically unsaturated acid monomer, and a ureido group as the crosslinkable monomer. 0.1 to 5% by weight of an unsaturated monomer comprising a, The conjugated diene monomer is at least one selected from the group consisting of 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, 1,3-pentadiene and isoprene ego, The ethylenically unsaturated nitrile monomer is at least one selected from the group consisting of acrylonitrile, methacrylonitrile, fumaronitrile, α-chloronitrile, and α-cyano ethyl acrylonitrile, The ethylenically unsaturated acid monomer is composed of acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, maleic anhydride, citraconic anhydride, styrene sulfonic acid, monobutyl fumarate, monobutyl maleic acid and mono-2-hydroxypropyl maleic acid. Selected from the group, The unsaturated monomer containing the ureido group as a crosslinkable functional group is 1 selected from the group consisting of 2-ethylene ureidoethyl methacrylate, 2-ethylene ureidoethyl methacrylamide and bis (2-ethylene ureidoethyl) maleate. Carbonic acid modified nitrile copolymer latex characterized by the above-mentioned. delete delete delete delete delete According to claim 1, wherein the carboxylic acid-modified nitrile copolymer latex carboxylic acid-modified nitrile further comprises an ethylenically unsaturated monomer copolymerizable with the monomer constituting the copolymer within 20% by weight of the total copolymer Copolymer latex. The method of claim 7, wherein the copolymerizable ethylenically unsaturated monomer is one selected from the group consisting of vinyl aromatic monomers, fluoroalkylvinyl ethers, ethylenically unsaturated amide monomers, nonconjugated diene monomers, and ethylenically unsaturated carboxylic ester monomers. Carbonic acid modified nitrile copolymer latex characterized by the above. The method of claim 1, wherein the latex comprises 0.3 to 10 parts by weight of an emulsifier, 0.01 to 2 parts by weight of a polymerization initiator, and 0.1 to 0.9 parts by weight of a molecular weight regulator based on 100 parts by weight of the total monomers constituting the carboxylic acid-modified nitrile copolymer. Carbonic acid modified nitrile copolymer latex, characterized in that. Dip molding latex composition comprising a carboxylic acid-modified nitrile copolymer latex according to claim 1. The latex composition for dip molding according to claim 10, wherein the carboxylic acid-modified nitrile copolymer latex is included in an amount of 80 to 99% by weight of the total composition. A dip molded product obtained by dip molding the latex composition for dip molding according to claim 10. The dip molded article according to claim 12, wherein the dip molded article is a dip molded latex article selected from gloves, inspection gloves, condoms, catheters or various kinds of industrial and household gloves and health care products.